After investigating a bit I found the reason behind this strange behavior(only in our perspective) is,

There is an option called ‘deferred_segment_creation’ starting from 11.2 which just adds an entry into the data dictionary but won’t actually create a segment.
So even in case of a locally managed tablespace, Oracle need not update the bitmaps in the current tablespace (RO in our case).
As it is just adding an entry into some of the data dictionary tables, Oracle doesn’t throw any errors.

You can’t even find a segment created in this tablespace

SQL> select segment_name,segment_type from dba_segments where tablespace_name=’RO’;
no rows selected

If you try to create a table by forcing it not to use the deferred_segment mode like this,